Prenatal Exposure to High Butterfat and BPA Affected Sperm Development in Rats

NIEHS grantees report that male rats prenatally exposed to a diet of high butter fat and bisphenol A (BPA) showed impaired sperm development that was more severe than those exposed to BPA or high butter fat alone. This is one of the first studies examining the potential additive effects of BPA and high butter fat.

To evaluate the effects of BPA and fatty acids on male reproductive function, the researchers fed pregnant rats a diet containing low percent butterfat, high percent butterfat, or high percent olive oil, with or without BPA. To mimic an aging hormonal milieu, some male offspring from these rats received hormonal treatment from the time they were 70 to 210 days old. Another group of male offspring was naturally aged to 18 months, the equivalent of 45 human years.

In both the hormone-treated group and the naturally-aging group, the researchers observed impairment in the process of sperm development, known as spermatogenesis. This effect occurred in adult male rats with gestational exposure to BPA alone, the high butterfat diet alone, or high butterfat and BPA together. Compared with the single-treatment groups, the high butter fat and BPA group experienced more severe effects, including atrophy. In contrast, gestational exposure to the olive oil diet or olive oil with BPA did not affect spermatogenesis. The researchers say that more research is needed to understand how BPA and a high butter fat diet might interact to increase spermatogenesis defects.